1. Field of the Invention
The present invention relates to a fin stabilizer for a vessel for suppressing a rocking motion of the vessel body.
This application is based on Japanese Patent Application No. 2005-118421, the content of which is incorporated herein by reference.
2. Description of Related Art
Conventionally, as an apparatus for suppressing the rolling motion and pitching motion of a vessel body there is known, for example, a fin stabilizer (for example, refer to Japanese Unexamined Patent Application, First Publication No. H08-324485). This fin stabilizer has a fin provided on and projecting from an outer panel of the vessel and by controlling an angle of this fin a lifting force is generated to suppress the rolling motion of the vessel body.
In such a fin stabilizer, a fin angle with respect to sea water flow (hereunder referred to as “angle of attack”) and a fin angle with respect to the vessel body (hereunder referred to as “fin angle”) are treated as identical, and anti-rolling control for the vessel is carried out by controlling the fin angle based on the rocking motion of the vessel body.
However, under the influence of wave disturbance and motion of the vessel body, the above angle of attack and fin angle may not match in some cases. In this case, in the above mentioned conventional fin stabilizer, there has been a problem in that the fin angle cannot be controlled at an appropriate angle and a required lifting force for suppressing rocking motion of the vessel body cannot be achieved.